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Discussion Starter · #1 ·
I received a UX yesterday after waiting a mere 9 months :roll:
It's definitely a nice watch but it seems to have an odd "bounce" to the second hand :-S
Just the slightest "overshot" then back-up.
Very minimal I assure you but more pronounced in certain areas as it goes around the dial.
I don't own many quartz watches so maybe this is a common problem/occurence?
Would it be perhaps a binding in the mounting of the second hand in certain areas?
Seems to be spot-on in accuracy since setting it as expected and it's not noticeable enough to be a real annoyance but I just want to be sure it's not a symptom of a larger or developing problem.
Grateful for your guidance and opinions gents!
 

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I've noticed this type of bounce on occasion. I don't know the cause, although I've heard that some micromotor designs have a final backlash correction as part of their moves. It's probably not a concern, but you should ask the dealer if you're concerned.

Perhaps others have seen this on their ETA movements? I don't have any, so I can't comment further.
 

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Maybe, just maybe...

The watch is driven by a stepper motor "cogging" from one pole to the next and next. When the stepper steps it'll push the rotor from its current magnetically locked (rather than physically locked in the way that a mechanical escapement stops its movement) position to the next magnetic lock. Since it's a magnetic field that holds it stationary so maybe the rotor has sufficient inertia to make the field unable to stop it dead. It'll overshoot slightly and then be drawn back into line.

I'm having a beer with some motor design specialists next week so I'll try to get a theory from them.
 

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Re: Maybe, just maybe...

That is pretty much what happens with permanent magnet stepper motors. When the electronics fire they kick the rotor out of the grip on one set of "cogs" to the next. When it arrives at the next "lock point" it has inertia to dissipate, this may cause a little overshoot before the rotor is dragged back to where it should be.
 

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Discussion Starter · #8 ·
Re: Maybe, just maybe...

Thanks for clearing it up roba, I'm sure it's fine, still perfectly accurate.
I'll just consider it part of it's "character" and sound educated when explaining it to others...lol.
 
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